# #1

# def f(x):
#     y = 3*(x**4) - 9*(x**2) + x/2
#     return y
# list=[54,96,83,64,234,158,364]
# for i in list:
#     print(f(i),end = ' ')

#2

# def grade(x:int):
#     if x >= 90:
#         return 'A'
#     if 90 > x >= 80:
#         return 'B'
#     if 80 >x>= 60:
#         return 'C'
#     if x < 60:
#         return 'D'
# x = int(input('请输入成绩：'))
# print('成绩的等级：{}'.format(grade(x)))

# #3

# N = list(map(int,input("请输入列表(各数之间用“,”隔开)：").split(',')))
# for i in N:
#     if i %2 == 0:
#        N.remove(i)
# print("已知列表奇数位所组成的新列表：{}".format(N))

# #4

# list = ['1','2','3','4']
# l = []
# for i in list:
#     for j in list:
#         for k in list:
#             a = i+j+k
#             if a not in  l:
#                 l.append(a)
# print("能组成{}个互不相同且无重复数字的三位数".format(len(l)))
# for i in l:
#     print(i,end = ' ')


# #5

# a = list(map(int,input("输入三个整数x,y,z并用“,”隔开：").split(',')))
# a.sort()
# for i in a:
#     print(i,end = ' ')

# #6

# def ou(n):
#     s = 0
#     for i in range(2,n+1,2):
#         s += 1/i
#     return s
# def ji(n):
#     s = 0
#     for i in range(1,n+1,2):
#         s += 1/i
#     return s
# n = int(input("请输入一个整数："))
# if n%2 == 0:
#     print(ou(n))
# else:
#     print(ji(n))

# #7
# s = input('请输入一行字符串：')
# a = []
# b = []
# c = []
# d = []
# for i in iter(s):
#     if i.isalpha():
#         a.append(i)
#     elif i.isdigit():
#         b.append(i)
#     elif i.isspace():
#         c.append(i)
# print("英文字符：{}个数：{},数字：{}个数:{},空格：{}个数：{},其它字符：{}个数：{}".format(len(a),len(b),len(c),len(d)))

